<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.js"></script>
</head>

<body>
    <div id="test">hello world</div>
    <button id="btn">切换</button>
    <script>
        $("#btn").click(function () {
            // toggle() 继承了Hide(),show()
            $("#test").toggle();
        })
    </script>
</body>

</html>